The full moon shone bright over the walls of Ba Sing Se, as a certain tranquility settled over the city. After a busy day, the denizens of the city had retired to their homes, leaving only a few street sweepers and drunks stumbling home from pubs.
And then the silence of the night was interrupted as a Sky-bison swooped over the streets, travelling fast and low. An eclectic group of young adults rode in its saddle, clutching weapons and with determined expressions on their faces.
There was Suki, resplendent in the green and black armour and white face paint of her warrior order, sat next to Sokka, who wore dark blue armour and a wolf's head helmet, holding his hand. Next to them, the blind Earthbender Toph Beifong, who hated flying, clutched onto Sokka's arm. Dressed in black and with his hair in a topknot, the young Firelord, Zuko, stared out over the city, his hands playing over the hilt of his twin swords, while next to him his wife, Firelady Mai, checked her sleeves to make sure her spring-loaded knife launchers were all present and correct. A rather bored expression played on her face, despite the circumstances.
Ahead of them, on the bison's head, sat the final two members of their little group. Sokka's sister, the waterbending master Katara, stared out in front of her, one hand already idly moving over a pair of water skins she kept on her hip. Tonight was a full moon, and as a result she was at her most powerful. If she so chose, she could to things that even she thought too terrible to imagine with her power on this night, but Katara had not only power but the restraint not to use it. Her other hand was being held by a teenager in orange and yellow robes.
This was Aang, and he was a relic of a bygone age. As the last airbender, the only survivor of a terrible tragedy that had befallen his people a century earlier, Aang had always considered that he had a special duty to keep their traditions alive, but he hid it behind a facade of happiness, joviality and laughter.
The fact that he was the Avatar on top of all this only added to his responsibility. Whatever else he was though, he was most importantly Katara's boyfriend, and he could count on her full and unwavering support, as she knew she could on his.
Together, this group of young people had, five years previously, taken on the tyranny of the Fire Nation's Old Regime, spearheaded by the previous Firelord Ozai and his daughter Azula, and defeated them. Aang had defeated Ozai in a straight fight on the day of Sozin's comet, removing his bending and consigning him to life in prison, while Zuko and Katara had worked together to take down Azula. Though the war had ended on the day Sozin's Comet came, the responsibilities he and his friends had to the world had not. The scars of war still ravaged the landscape, and it was up to him to fix it.
Katara was interrupted in her thoughts, as she so often was, by Sokka shouting.
"Remember, we need to strike hard and fast! Surprise will be important, and so we need shock and awe to succeed!"
"Don't worry Snoozles, shock and awe are my middle names!" Toph replied. The group laughed, even Mai.
Their target became visible in the city below them; a large warehouse with a courtyard outside it. A very large organised crime ring had been operating out of that warehouse, and it had even put a hit on Earth King Kuei's pet bear, Bosco. Katara supposed that they were trying to send some kind of message for the King to stay out of their way. The assassin had, though, failed because he tried to fight a bear with a small knife, but it had been thought appropriate to bring everyone to deal with them.
Appa flew over the top of the warehouse, and Aang stood up in the saddle.
"Alright, wish me luck!" He told them. Katara joined in as everyone did so, considering how dashing he looked in that moment. Then, the Avatar looked down at the roof, and jumped.
There was a moment of silence as he flew down, followed by a sudden crash as he sent a blast of air to slam through the roof, creating a sudden opening that he dropped through. Katara guided Appa downwards, to follow them, as the first sounds of combat could be heard beneath them.
As Appa passed through the hole in the roof, the first gangsters spotted them. However, they barely had time to shout before they found themselves pinned to the wall by an ultra-accurate hail of knives from Mai, and then she and Zuko were gone, the Firelord igniting his blades and spinning them as they leapt onto the gantry. Soon, they were followed by Sokka, Suki and Toph, the two non-benders' weapons flashing gold and black in the light as they threw themselves into battle. Katara heard a wild war-cry coming from her brother's mouth, and then they too were gone.
Katara, meanwhile, concentrated on landing Appa successfully. An unfortunate gangster, hearing the sounds of combat from above him, wandered out into the centre of the floor for a better look and Appa landed on him. Katara did not spare a thought for him as she jumped off, and with a gesture both her water skins opened, a stream of liquid pouring out and forming a pair of gigantic whips that froze a one gangster to a wall and collapsed a gantry on top of another.
She quickly ran to climb the stairs, to meet up with the rest of her group. She heard the sounds of swords clashing, battlecries and twisting metal above her, and one particularly loud scream that caused her to turn and see a man plummet past her. She didn't know who had been responsible for that. The first of her friends she saw was Aang, who was at that moment blasting a gangster into a wall.
"Hey, Katara!" He said brightly, waving to her.
"Shouldn't you be concentrating?" She asked.
"I'm sorry, but it's hard to concentrate on a fight when you're here, you know that!" As Aang said this, he stamped his feet and the floor twisted underneath him, knocking over a man who had been charging at him from behind with an axe raised above his head.
"Well try, at least," Katara told him, smiling. "We'll have enough time for... other things later."
"I'll hold you to that," Aang grinned again, before turning back to the fight. Katara moved on.
The next battle she saw was between about five gangsters and the Firelord and Firelady. Zuko's twin swords were aflame, and created entrancing patterns of light in the air as they danced about, parrying and slashing at any man within reach. Mai moved with him in perfect harmony, launching perfectly aimed knives that stuck men to walls at range before moving back to let Zuko deal with any of them who got too close. Katara decided that they had the situation well in hand, and so moved on.
When she eventually found the other three, having frozen another three gangsters to a wall in the process, she found them in the middle of an argument.
"...Come on, save some for us, Toph!" Sokka and Suki were remonstrating with the blind Earthbender.
"It's not my fault I'm taking them out before you got a chance to," Toph replied.
"Hey, there are still gangsters down there," Katara interrupted, pointing down the stairs the way she had come.
"Well, they aren't going to beat themselves up," Suki said, offering her hand to Sokka. Together, they ran past Katara, and soon more sounds of fighting could be heard. As Toph went to move past her though, Katara stopped her.
"Hey, Toph, you don't happen to know where the owner of this operation is?" She asked, hopefully.
Toph only shook her head. "I'm sure I could find him if I knew what his vibrations felt like, but I don't. Sorry."
Katara was just about to tell her that she had nothing to be sorry for when they heard a sound that made her blood run cold:
The sound of Aang shouting in pain.
All thoughts of their previous conversation forgotten, Katara took off towards the sound, Toph just behind her. A few gangsters tried to stop them, but Katara had no patience for that and so knocked them straight off the platform. Eventually, they came to a door, behind which the sounds were coming from. Katara used her water to smash the door clean off its hinges and came bursting in to find Aang, on his knees, with his arms bent at an unnatural angle and his head tilted back. His eyes were wide with shock.
Behind him, a man in black stood, with one hand on Aang's forehead. Katara launched her water at the man, screaming in anger, but he easily dodged. Aang collapsed to the floor, groaning softly.
Katara was just about to launch another furious attack at him when she felt herself freeze. Her shock and anger returned again as she realized she knew this feeling. This man was a blood bender.
He didn't have long to revel in his victory though, for Toph burst in and collapsed a wall on top of him. The man fell away, and instantly Katara felt his hold on her broken. She ran to Aang, shouting his name, and preparing to heal him.
"Hey... Katara, he said, smiling despite everything at the sight of her face. "Where is he?"
"He's gone," Katara told him. Toph concentrated for a second, and then confirmed it.
Just then, the rest of Team Avatar burst in.
"What's going on?" Sokka asked.
"We heard shouting," Suki added.
"Oh, Agni... is Aang alright?" Zuko clocked the Avatar on the floor.
"I'm fine. He did something, but I don't feel different!"
Aang made an effort to sit up. He thrust his arm downwards, to create a blast of air that would send him floating to his feet.
Nothing happened.
Aang frowned, and tried again. And again. And then the frown became a look of distress.
He punched his fist outwards, hoping to generate a fireball perhaps, and that did nothing either.
"Oh no," Katara heard Mai breath behind her.
As Aang finally gave up and collapsed to the ground, Katara hugged him tightly, as she heard the distraught Avatar repeating one question over and over again:
"I... can't bend. Why can't I bend?"
Had they looked up, they would have noticed the shock and sadness on the faces of all their friends.